PixelBuffer.cpp revision cf51a4199835e9604aa4c8b3854306f8fbabbf33 
1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <utils/Log.h>
20
21#include "Caches.h"
22#include "Extensions.h"
23#include "PixelBuffer.h"
24#include "Properties.h"
25
26namespace android {
27namespace uirenderer {
28
29///////////////////////////////////////////////////////////////////////////////
30// CPU pixel buffer
31///////////////////////////////////////////////////////////////////////////////
32
33class CpuPixelBuffer: public PixelBuffer {
34public:
35    CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
36    ~CpuPixelBuffer();
37
38    uint8_t* map(AccessMode mode = kAccessMode_ReadWrite);
39    void unmap();
40
41    uint8_t* getMappedPointer() const;
42
43    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset);
44
45private:
46    uint8_t* mBuffer;
47};
48
49CpuPixelBuffer::CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height):
50        PixelBuffer(format, width, height) {
51    mBuffer = new uint8_t[width * height * formatSize(format)];
52}
53
54CpuPixelBuffer::~CpuPixelBuffer() {
55    delete[] mBuffer;
56}
57
58uint8_t* CpuPixelBuffer::map(AccessMode mode) {
59    if (mAccessMode == kAccessMode_None) {
60        mAccessMode = mode;
61    }
62    return mBuffer;
63}
64
65void CpuPixelBuffer::unmap() {
66    mAccessMode = kAccessMode_None;
67}
68
69uint8_t* CpuPixelBuffer::getMappedPointer() const {
70    return mAccessMode == kAccessMode_None ? NULL : mBuffer;
71}
72
73void CpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
74    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height,
75            mFormat, GL_UNSIGNED_BYTE, mBuffer + offset);
76}
77
78///////////////////////////////////////////////////////////////////////////////
79// GPU pixel buffer
80///////////////////////////////////////////////////////////////////////////////
81
82class GpuPixelBuffer: public PixelBuffer {
83public:
84    GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
85    ~GpuPixelBuffer();
86
87    uint8_t* map(AccessMode mode = kAccessMode_ReadWrite);
88    void unmap();
89
90    uint8_t* getMappedPointer() const;
91
92    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset);
93
94private:
95    GLuint mBuffer;
96    uint8_t* mMappedPointer;
97    Caches& mCaches;
98};
99
100GpuPixelBuffer::GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height):
101        PixelBuffer(format, width, height), mMappedPointer(0), mCaches(Caches::getInstance()) {
102    glGenBuffers(1, &mBuffer);
103    mCaches.bindPixelBuffer(mBuffer);
104    glBufferData(GL_PIXEL_UNPACK_BUFFER, getSize(), NULL, GL_DYNAMIC_DRAW);
105    mCaches.unbindPixelBuffer();
106}
107
108GpuPixelBuffer::~GpuPixelBuffer() {
109    glDeleteBuffers(1, &mBuffer);
110}
111
112uint8_t* GpuPixelBuffer::map(AccessMode mode) {
113    if (mAccessMode == kAccessMode_None) {
114        mCaches.bindPixelBuffer(mBuffer);
115        mMappedPointer = (uint8_t*) glMapBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, getSize(), mode);
116        mAccessMode = mode;
117    }
118
119    return mMappedPointer;
120}
121
122void GpuPixelBuffer::unmap() {
123    if (mAccessMode != kAccessMode_None) {
124        if (mMappedPointer) {
125            mCaches.bindPixelBuffer(mBuffer);
126            glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
127        }
128        mAccessMode = kAccessMode_None;
129        mMappedPointer = NULL;
130    }
131}
132
133uint8_t* GpuPixelBuffer::getMappedPointer() const {
134    return mMappedPointer;
135}
136
137void GpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
138    // If the buffer is not mapped, unmap() will not bind it
139    mCaches.bindPixelBuffer(mBuffer);
140    unmap();
141    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height, mFormat,
142            GL_UNSIGNED_BYTE, (void*) offset);
143}
144
145///////////////////////////////////////////////////////////////////////////////
146// Factory
147///////////////////////////////////////////////////////////////////////////////
148
149PixelBuffer* PixelBuffer::create(GLenum format, uint32_t width, uint32_t height, BufferType type) {
150    bool gpuBuffer = type == kBufferType_Auto && Extensions::getInstance().getMajorGlVersion() >= 3;
151    if (gpuBuffer) {
152        char property[PROPERTY_VALUE_MAX];
153        if (property_get(PROPERTY_ENABLE_GPU_PIXEL_BUFFERS, property, "false") > 0) {
154            if (!strcmp(property, "true")) {
155                return new GpuPixelBuffer(format, width, height);
156            }
157        }
158    }
159    return new CpuPixelBuffer(format, width, height);
160}
161
162}; // namespace uirenderer
163}; // namespace android
164